ALTER USER

ALTER USER 语句用于更改 TiDB 权限系统内的已有用户。和 MySQL 一样,在 TiDB 权限系统中,用户是用户名和用户名所连接主机的组合。因此,可创建一个用户 'newuser2'@'192.168.1.1',使其只能通过 IP 地址 192.168.1.1 进行连接。相同的用户名从不同主机登录时可能会拥有不同的权限。

语法图

AlterUserStmt

ALTER USER - 图1

UserSpecList

ALTER USER - 图2

UserSpec

ALTER USER - 图3

Username

ALTER USER - 图4

AuthOption

ALTER USER - 图5

PasswordOption

ALTER USER - 图6

LockOption

ALTER USER - 图7

AttributeOption

ALTER USER - 图8

1. AlterUserStmt ::=
2. 'ALTER' 'USER' IfExists (UserSpecList RequireClauseOpt ConnectionOptions PasswordOption LockOption AttributeOption | 'USER' '(' ')' 'IDENTIFIED' 'BY' AuthString)

4. UserSpecList ::=
5. UserSpec ( ',' UserSpec )*

7. UserSpec ::=
8. Username AuthOption

10. Username ::=
11. StringName ('@' StringName | singleAtIdentifier)? | 'CURRENT_USER' OptionalBraces

13. AuthOption ::=
14. ( 'IDENTIFIED' ( 'BY' ( AuthString | 'PASSWORD' HashString ) | 'WITH' StringName ( 'BY' AuthString | 'AS' HashString )? ) )?

16. PasswordOption ::= ( 'PASSWORD' 'EXPIRE' ( 'DEFAULT' | 'NEVER' | 'INTERVAL' N 'DAY' )? | 'PASSWORD' 'HISTORY' ( 'DEFAULT' | N ) | 'PASSWORD' 'REUSE' 'INTERVAL' ( 'DEFAULT' | N 'DAY' ) | 'FAILED_LOGIN_ATTEMPTS' N | 'PASSWORD_LOCK_TIME' ( N | 'UNBOUNDED' ) )*

18. LockOption ::= ( 'ACCOUNT' 'LOCK' | 'ACCOUNT' 'UNLOCK' )?

20. AttributeOption ::= ( 'COMMENT' CommentString | 'ATTRIBUTE' AttributeString )?

示例

1. CREATE USER 'newuser' IDENTIFIED BY 'newuserpassword';
1. Query OK, 1 row affected (0.01 sec)
1. SHOW CREATE USER 'newuser';
1. +----------------------------------------------------------------------------------------------------------------------------------------------------------------------+
2. | CREATE USER for newuser@%                                                                                                                                            |
3. +----------------------------------------------------------------------------------------------------------------------------------------------------------------------+
4. | CREATE USER 'newuser'@'%' IDENTIFIED WITH 'mysql_native_password' AS '*5806E04BBEE79E1899964C6A04D68BCA69B1A879' REQUIRE NONE PASSWORD EXPIRE DEFAULT ACCOUNT UNLOCK |
5. +----------------------------------------------------------------------------------------------------------------------------------------------------------------------+
6. 1 row in set (0.00 sec)
1. ALTER USER 'newuser' IDENTIFIED BY 'newnewpassword';
1. Query OK, 0 rows affected (0.02 sec)
1. SHOW CREATE USER 'newuser';
1. +----------------------------------------------------------------------------------------------------------------------------------------------------------------------+
2. | CREATE USER for newuser@%                                                                                                                                            |
3. +----------------------------------------------------------------------------------------------------------------------------------------------------------------------+
4. | CREATE USER 'newuser'@'%' IDENTIFIED WITH 'mysql_native_password' AS '*FB8A1EA1353E8775CA836233E367FBDFCB37BE73' REQUIRE NONE PASSWORD EXPIRE DEFAULT ACCOUNT UNLOCK |
5. +----------------------------------------------------------------------------------------------------------------------------------------------------------------------+
6. 1 row in set (0.00 sec)
1. ALTER USER 'newuser' ACCOUNT LOCK;
1. Query OK, 0 rows affected (0.02 sec)

修改 newuser 的属性:

1. ALTER USER 'newuser' ATTRIBUTE '{"newAttr": "value", "deprecatedAttr": null}';
2. SELECT * FROM information_schema.user_attributes;
1. +-----------+------+--------------------------+
2. | USER      | HOST | ATTRIBUTE                |
3. +-----------+------+--------------------------+
4. | newuser   | %    | {"newAttr": "value"}     |
5. +-----------+------+--------------------------+
6. 1 rows in set (0.00 sec)

通过 ALTER USER ... COMMENT 修改用户 newuser 的注释:

1. ALTER USER 'newuser' COMMENT 'Here is the comment';
2. SELECT * FROM information_schema.user_attributes;
1. +-----------+------+--------------------------------------------------------+
2. | USER      | HOST | ATTRIBUTE                                              |
3. +-----------+------+--------------------------------------------------------+
4. | newuser   | %    | {"comment": "Here is the comment", "newAttr": "value"} |
5. +-----------+------+--------------------------------------------------------+
6. 1 rows in set (0.00 sec)

通过 ALTER USER ... ATTRIBUTE 删除用户 newuser 的注释:

1. ALTER USER 'newuser' ATTRIBUTE '{"comment": null}';
2. SELECT * FROM information_schema.user_attributes;
1. +-----------+------+---------------------------+
2. | USER      | HOST | ATTRIBUTE                 |
3. +-----------+------+---------------------------+
4. | newuser   | %    | {"newAttr": "value"}      |
5. +-----------+------+---------------------------+
6. 1 rows in set (0.00 sec)

通过 ALTER USER ... PASSWORD EXPIRE NEVER 修改用户 newuser 的自动密码过期策略为永不过期:

1. ALTER USER 'newuser' PASSWORD EXPIRE NEVER;
1. Query OK, 0 rows affected (0.02 sec)

通过 ALTER USER ... PASSWORD REUSE INTERVAL ... DAY 修改用户 newuser 的密码重用策略为不允许重复使用最近 90 天内使用过的密码:

1. ALTER USER 'newuser' PASSWORD REUSE INTERVAL 90 DAY;
1. Query OK, 0 rows affected (0.02 sec)

另请参阅